Accumulator-control mechanism



Oct. 13,1925.

H. H. HUMMEL ACCUMULATOR CONTROL MECHANISM Fild May 28, 1925 2 Sheets-Sheet 1 61 Ma n My.

Patented Oct. 13, 1925.

* UNITED STATES PATENT OFFICEQ HOWARD H; HUMMEL, 0E BETHLEHEM, PENNSYLVANIA, AssIcNoH fro BETHLEHEM STEEL COMPANY, oEBE'rHLEHEM, PENNSYLVANIA, A CORPORATION or 'ENN- SYLVANIA.

ACCUMULATOR-GONTROI MECHANISM.

Application filed May 28, 1923.. serial No. 642,092

To all whom it may concern:

Be it known that I, HoWARD H. HUMMEIL,

a citizen of the United States, and a resident of Bethlehem, Lehigh County, State of Pennsylvania, have invented certain new and useful Improvements in Accumulator-Control Mechanism, of which the following is a specification. I i i This invention relates to improvements in mechanism'for controlling the flow of fluids particularly under high pressure, andis especially adapted for use with accumulators in connection with an hydraulic powersystem.

The object of the invention is to provide mechanism that will prevent water hammering in the pipes incident to the abrupt stoppage of the accumulator in any, position of its stroke, and eliminate excessive pressures thus occasioned; another object of the invention is to provide automatic means which will function to choke or restrict the flow from the accumulator when an abnormal amount of fluid is suddenly required; a further object of the invention is to provide a device which is self acting and will automatically c hoke the accumulator to effectively prevent egress of water therefrom when a break occurs in the pressure line; a still further object is to provide mechanism operated by the pressure of the fluid for automatically restricting flow of fluid from the accumulator; moreover, the invention provides a cushioning means for the accumulator in combination with an automatic choking device whereby the latter will act effectively without being subjected to undue stress.

The accompanying drawings forming a part of this specification illustrate one specific form of the invention, although it is to be understood, that the same may be embodied in other constructions differing in details from that illustrated.

In the drawings:

Figure 1 is a diagrammatic view of an hydraulic system with the presentinvention applied thereto.

Figure 2 is a vertical section through the control mechanism.

Figure 3'is a horizontal section substantially on the line 3-3 of Figure 2.

Figure 4; is a detail section on the line 4L4; of Figure 3.

Figure 5 is a view of the iunerend. of the be supplied from the line 10.

manually adjustable choke valve hereinafter described; V Figure 6 is a vertical 'section through the accumulator and the supporting means for thesame. l 1

Referring to the drawings in detail, the system illustrated in Figure 1 comprises a main pipe line lOto which liquid is supplied under pressure from any suitable source such RS131 pumpor series of pumps, the manifold of which is indicated at 11. The numeral12 indicates a manifold for hydraulic presses,

or other mechanism to which'the liquid isto Branched from the line 10 isa secondary pipe line 105 -40 Which communicates with the accumulator A through the control mechanism generally designated at M. 7 a Y Y The control mechanism includes a valve block 13, which is bored to provide a plurality of ports or passages. To facilitate manufacture these passages are preferably bored from the exterior faces of the block vand the outer ends are closed by suitable plugs as hereinafter noted. The passagel which is in communication with the pipe '10 extends longitudinally of the'block 13, and

at its inner end this passage communicates with atransverse passage 15 in which there 1s secured an annular bushing or valve seat 16 having at its upper end a beveled face 16. A passage 17 communicates with the passage 14 intermediateits length, and an annular bushing or valve seat 18 is secured in this passage Above and preferably parallel with the passage 14 is a second longitudinal passage 19, the outer end of which is closed by a threaded plug 19. Near its outer end the passage 19 communicates with'a branch passage 20, the latter being in communication with the pipe 10'. The passage 19 intermediate its ends intersects or communicates with the passage 17 above mentioned. At its innerend the passage 19-communicates with a passage 21 in whichthere is secured an annular bushing or valve seat'22.

Passage 21 communicates with a passage 23,

which in turn communicates. with .a' passage 24, the latter being in communlcation with the passage 15 above mentioned. The outer' ends of passages 23:and 24 are closed, respectively, by threaded plugs 23 and 24,

A check valve 25 is adapted to cooperate with the seat 18 in the passage 17 this valve "tating it in the plug 31.

' A manually adjustable choke valve is arranged at the point where the passages 19 and 21 intersect. This valve is carried by a plug 31 threaded into the block 13 and provided with internal threads to cooperate with threads on the stem of the valve 30. A suitable packing 32 is interposed between the inner end of the plug 31', and a shoulder on the block 13'to insure water tightness.

The inner end 'of the valve 30-is of conical form and the same may be manually adjusted towardand' from the seat 22 by ro- This valve may therefore be set to restrict to any desired extent the flow ofliquid through the passage 21, To maintain the valve 30 in any desired position of adjustment there is provided a locking block 33 mounted on a-stud 34 secured to the block 13, the locking block being fasten'ed to the stud by means of a pin 35 passing through aligned openings in these parts. The locking block 33 carries a pin 33 which is adapted to enter any one of a number of holes" 36 provided in a flange 30 on thestem of the valve 30. .It will 6 thus be seen that after the valve 30' has been adjusted to any desired position .and the locking block placed over the'stud34 with the pin 33?,in one of'the openings in the flange 30 ofthe valve and with ,thepin 35 in "position, the valve" will be locked against movement. v I

.At the point wherethepassages 15 and 24 intersect or, communicate there is provided a movable choke'valve 40, such valve being formed by? providing a conical end on a valve plunger 41 Which-'eiitends to the outside of thebloek 13, and which is slidably mounted in a plug 42threaded into said block. A su'itable, packing .43 is interposed between theinner end of the plug, and a shoulder on the block toinsure water tight ness. It will be apparent that when the valve is moved inwardly it will cooperate with the seat 16 to restrict flow of liquid from the accumulator through the passages 21,23, 24 and 15.

, operating plunger 45fextends from the outside of the block 13 into the passage 19 near the outer end of. the latter, this plunger being slidably mounted in a plug 46, threaded into the bloek13 A suitable packing arranged between the. ini'ierend of the plug 46 and a shoulder on the block 13 insures water-tightness. Preferably the passage 19 is provided with a laterally extending portion 47 to provide space for movement of the plunger 45. The cross sectional area of the plunger 45 is substantially less than that of the plunger 41, the results of which will presently be pointed out. I

A lever 50 is pivotally supported on the block 30 as by means of a standard 51, and

this lever is provided with a slot 52 at each side of its pivot point and preferably equidistant therefrom. The extended or free end of the lever 50 carries a roller 53 for a purpose hereinafter mentioned. The ends of the plungers 41 and 45 are attached to clevises 54 pivotally connected to trunnion blocks slidably I mounted in each of the aforementioned slots formed in the lever 50. It follows that when the lever 50 is osoillated,'the p'lungers 41 and 45 move in opposite directions, one inwardly and the other outwardly relative to the passages in the block 13-.

Normallythe pressure of the fluid in the various passages of the block 13 is the same throughout, and under such condition the valve plunger 41 is subjected to' a greater total pressure than the operating plunger 45 due to its larger cross" sectional area, and such plunger 41 is therefore normally retained in its upper or outer position with the conical valve portion 40 removed from its seat 16.- In case the pressure adjacent the plunger 41 decreases, the higher pressure exerted upon the plunger 45 will tend to move such plunger outwardly and thus move the valve 40 toward its seat andre- While the preponderance given to the choke plunger 41 is preferably obtained by the difference in cross sectional area between it and the plunger 45, this preponderance may also be obtained by having'two plungers of. the same diameter. and having the distance from the fulcruniof the lever to comprises a plunger 60 operating in a cylinder 61 to which the pipe 10 is connected. Rigidly attached to the plunger60 is a cross head 62, upon'whioh' are supported a series of springs 63. A spring eap 64 is arranged on top of these springs and a series of rods 65 are connected to this cap and extending downwardly through the springs and through openings in the cross head 62. On the lower'ends of these rods the accumulatorweight or'weights 66 are supported. The springs 63 are under a pre determined initial compression which is so adjusted in conjunction with the choke valve 30 that when flow of liquid from the aceumulator is suddenly discontinued, the kinetic energy of the descending weights 66 is never allowed to attain such magnitude as to completely compress said springs totheir solid height. Secured to the weight 66 near the bottom thereof is a lug 67 so arranged as to contact with the roller 53 and operate the lever 60 just before the weight reaches its lowermost position.

In operation the pumps (not shown) supply fluid under pressure to the manifold 11 from which it is transmitted to the press manifold 12 through the pipe line 10. When fluid is thus being supplied or if more is supplied than demanded, the surplus passes through the branch pipe 10", through the passage 14, check valve and passage 19 of the block 13, and then through the pipe 10 to the accun'iulator, the weight 66 of which may be raised to its uppermost position. When in-this position the accumulator will continue to supply fluid to the manifold 12 even if the pumps are cut off, the fluid at such time flowing through the passages 21, 23, 24 and 15 which passages, in effect, form a by pass around the check valve 25. The choke valve in said by pass is adjusted so that under normal conditions the accumulator will settle at a fairlyuniform rate when the pumps are thus cut off. hen the presses (not shown) which are supplied from the manifold 12 are stopped, the flow of fluid from the accumulator is discontinued and the plunger 60 is brought to rest, the momentum of the falling weight 66 is gradually reduced by the-springs 63 which compress but return to normal when the inertia oflthe weight is overcome. If during operation any abnormal demand is imposed on the system, for example, on account of putting several presses into operation at once, or on account of a break in the pressure line, then the accumulator weight tends to drop rapidly; the pressure on the side of the choke valve 30 toward the pressure line or presses becomes materially reduced below that on the accumulator side of said valve, such drop in pressure being due to the action of the choke valve 30 in restricting flow of fluid through the conduit or by-pass formed by the passages 21, 28, 24 and 15. At such time, therefore, the, pressure on the operating plunger through the lever over-balances that on the valve plunger 41, the choke valve 40 is moved toward its seat 16 which results in stopping or restricting flow of fluid from the accumulator. When the pumps again supply the demand of the presses and build up pressure in the system, the lever 50 and choke valve 40 are returned to their original position. The action of the movable choke valve 40 therefore prevents the accumulator attempting to supply a sudden abnormal demand on a t e sy Otherwise the descending weight would attain such momentum that, extremely high and destructive pressures and objectionable water hammering would be produced in the pipe line when flow of fluid to the presses is discontinued.

It will be noted that the conoidal surface forming the choke valve 40 and the complementary surface 16 on the seat 16, produce an annular passage for fluid which gradually decreases as the valve is closed. This in combination with the resilient connec- .tion between the plunger and weight 66 aflorded by the springs 68 insures a smooth action and prevents abrupt stoppage which would be detrimental to the successful op eration of the automatic choking feature by imposing undue stresses on the choke valve and other parts. i

The automatic choking device disclosed in combination with the spring cushioning means for the accumulator weight, is very desirable in an hydraulic system which supplies fluid pressure to a plurality of hydraulic cylinders which operate mill machinery intermittently and at times in unison; the accumulator is in operation almost continuously and is subjected to abrupt changes in its direction of travel; the sudden stop thus occasioned would jar the automatic choking valve and seriously affect its operation but for the resilient connection between the accumulator weight and the plunger. However, should be understood that while the cushioning means in combination with the choking device is very desirable, it is not absolutely necessary to successful operation of the choking device perse, particularly when the latter is adapted to systems wherein the demand of the press seldom exceeds the normal supply or when the choking device is only embodied as a precaution against a break in the pressure line. p

Having thus described the invention what is claimed as new and desire to be secured by Letters Patent is:

1. In combination, an accumulator,means for supplying liquid thereto under pressure, a conduit through which liquid may flow from said accumulator, and means controlled by a preponderance of the pressure of the liquid on the inlet side of said conduit over the pressure on the outlet side thereof for restricting flow of the liquid from said accumulator through said conduit.

2. In combination, an accumulator, means for supplying liquid thereto under pressure, a conduit through which liquid may flow from said accumulator, 'a device for restricting flow of liquid from the accumulator, through said conduit, and automatically operated means rendered effective by a preponderance of liquid pressure on the inlet side of said device over the liquid pressure on the outlet side thereof for further restricting flow of liquid from said accumulator through said conduit.

3. In combination, a pipe-line, means for supplying liquid thereto under pressure, an accumulator into which liquid may flow from said line and from which liquid may flow to said line upon drop of pressure in thelatter, a conduit through which liquid may flow from said accumulator to said line, a stationary choke device for restricting flow of liquid through said conduit, a movable choke valve on the pipe-line side of said stationary device for further restricting flow of fluid through said conduit, means operated by liquid pressure on the accumulator side of said stationary device for mov ing said valve toward closed position when said accumulator pressure predominates the line pressure beyond a predetermined degree, and means operated by the pressure of the liquid on the pipe-line side of said stationary device for moving said valve toward open position, when the line pressure is restored from the source of liquid supply;

4. In combination, a pipeline, means for supplying liquid thereto under pressure, an accumulator into which liquid may flow from said line and from which liquid may flow to said line upon drop of pressure in the latter, a movable choke valve for restricting flow of liquid from said accumulator to said line, and means operated solely by a predetermined preponderance of the accumulator pressure over the line pressure for moving said valve into and out of position to restrict such flow.

5. In combination, a pipe-line, means for supplying liquid thereto under pressure. an accumulator into which liquid may flow from said line and from which liquid may flow to said line upon drop of pressure in the latter, a conduit through which liquid may flow from said accumulator to said line, a movable choke valve for restricting flow of liquid from said accumulator through said conduit, a plunger adapted to be operated by a predetermined preponderance of pressure of liquid on the accumulator side of said valve over the pressure of liquid on the line side thereof, and means foroperatively connecting said plunger and said valve.

6. In combination, a pipe-line, means for supplying liquid thereto under pressure, an accumulator into which ,liqulid may flow from said line and from which liquid may flow to said line upon drop of pressure in the latter, a conduit through which liquid may flow from said accumulator to said line, a stationary choke device for restricting flow of liquid through said conduit, a movablev plunger subjected to the pressure of liquid on the accumulator side of said device, a second movable plunger subjected to the pressure of the liquid on the pipeline side of said device, means operatively connecting said plungers, and means carried by said second named plunger for further restricting flow of fluid through said conduit when said second named plunger is moved by a predetermined preponderance of liquid pressure on the first named plunger over the liquid pressure on the second plunger.

7. In combination, a pipe-line, means for supplying liquid thereto under pressure, an accumulator into which liquid may flow from said line and from which liquid may flow to said line upon drop of pressure in the latter, a conduit through which liquid may flow from said accumulator to said line, a stationary choke device in said conduit, a plunger subjected to the pressure of the liquid on the accumulator side of said device, a second plunger subjected to the liquid pressure on the pipeline of said device, means for connecting said plungers so as to cause one to move inwardly as the other is moved outwardly relative to said conduit, said second plunger having means for further restricting flow of fluid through said conduit as the same is moved inwardly by a predetermined preponderance of pressure on said first named plunger over the liquid pressure on the second plunger.

8.'In combination, a pipe-line, means for supplying liquid thereto under pressure, an

accumulator into which liquid may flow from said line and from which liquid may flow to said line upon drop of pressure in the latter, a conduit through which liquid may flow from said accumulator to said line, a stationary choke device in said conduit, a plunger subjected to the pressure of the liquid on the accumulator side of said device, a second plunger subjected to the liquid pressure on the pipe-line side of said device, a lever for connecting said plungers so as to cause one to move inwardly as the other is moved outwardly relative to said conduit, said second plunger having means for further restricting flow of fluid through said conduit as the same is moved inwardly by a predetermined predominance of pressure on said first named plunger, the size of said plungers and their connection to said lever being such as to cause said second plunger to be moved outwardly when the pressure in said pipe line is normal.

9. Incombination, a pipe-line, means for supplying liquid thereto under pressure, an accumulator into which liquid may flow from said line and from which liquid may flow to said line upon drop of pressure inthe latter, a stationary choke device in said conduit, a plunger subjected to the pressure of the liquid on the accumulator side of said device, a second plunger subjected to the liquid pressure on the pipe-line side of said device, a lever to which said plungers are connected at substantially equal distances on opposite sides of the fulcrum thereof, whereby one of said plungers is caused to move inwardly as the other is moved outwardly relative to said conduit, said second plunger having means for further restricting flow of fluid through said conduit as the same is moved inwardly by a predetermined predominance of pressure on said first named plunger, said second plunger being of larger cross sectional area than said first plunger, whereby the same is caused to move outwardly against the pressure of the first plunger when normal pressure exists in said line.

10. In combination, a pipe-line, means for supplying liquid thereto under pressure, an accumulator, a conduit through which liquid may flow from said line toward said conduit, a check valve in said conduit opening toward said accumulator, a bypass conduit around said check valve, whereby liquid may fiow from said accumulator toward said line, and a movable choke valve operated by the pressure of the liquid for restricting flow of fluid from the accumulator through said by-pass conduit upon drop of pressure in said line.

11. In combination, a pipe-line, means for supplying liquid thereto under pressure, an accumulator, a conduit through which liquid may flow upon said line toward said conduit, a check valve in said conduit opening toward said accumulator, a by-pass conduit around said check valve, whereby liquid may flow from said accumulator toward said line, a manually operable choke valve in said b pass conduit for restricting fiow of liqmd therethrough, a movable choke valve in said by-pass conduit for further restricting the flow of liquid therethrough, and liquid pressure controlled means for operating said last named choke valve.

12. In combination, an accumulator having a plunger and a weight and cushioning means for supporting said Weight on said plunger, apipe-line, a conduit through which liquid may flow from said accumulator toward said line, and an automatic choke valve arranged to gradually restrict flow of fluid from the accumulator toward said line, when the accumulator pressure predominates the line pressure beyond a predetermined degree.

13. In comblnation, an accumulator having a plunger and a weight, cushioning means comprising a series of coiled springs for supporting said weight on said plunge-r, a pipe-line, a conduit through which liquid may flow from the accumulator toward said line, a choke valve for restriotimg flow of liquid through said conduit, means operated by the pressure of the liquid for moving said choke valve to gradually restrict flow of liquid through said conduit, when the accumulator pressure predominates the line pressure beyond a predetermined degree.

14;. In combination, a pipe-line, an hydraulic accumulator associated therewith, a conduit through which liquid may flow from said accumulator toward said line, a choke valve in said conduit for restricting flow of liquid therethrough, and means operated by the downward'movement of a part of the accumulator for closing said valve, said means being responsive to a predetermined pressure in the pipe line to restore it to its normal position when said part of the accumulator has been raised.

15. In combination, a pipe-line, an hydraulic accumulator associated therewith and having a weight, a conduit through which liquid may flow from said accumulator toward said line, a choke valve in said conduit, and means operated by the descent of said accumulator weight for closing said valve, said means being responsive to a predetermined pressure in the pipe line to restore it to its normal position when the ac cumulator weight has been raised.

16. Control mechanism for an hydraulic accumulator, comprising a block having a passage through which liquid may flow toward the accumulator, a check valve in said passage opening toward the accumulator, a bypass conduit in said block around said check valve and through which liquid may flow from the accumulator, and an, automatically operated choke valve for restricting flow of liquid through said by-pass conduit.

17 Control mechanism for an hydraulicaccumulator system, comprising a conduit through which liquid may fiow from the accumulator to a pipe line, a choke valve in said conduit,,a balanced pressure device for closing said valve, said device rendered effective only when the pipe line pressure has dropped below a predetermined minimum.

18. Control mechanism for an hydraulic accumulator system, comprising means for restricting flow of liquid from the accumulator, and means subject to a predominance of liquid pressure on the inlet side of said flow restricting means, for operating the latter.

In testimony whereof I hereunto afiix my signature.

HOWARD H. HUMMEIL. 

